1. Field of the Invention.
This invention relates to the field of forestry. More specifically, the invention comprises an integrated data collection system for use in sampling the timber characteristics within a predefined survey region.
2. Description of the Related Art.
Good timber management requires the periodic evaluation of the timber within a predefined region. Since a forest may contain a hundred or more trees per acre, it is impractical to measure every tree. Statistical sampling techniques have been developed to allow an accurate evaluation based on actual measurements of a small percentage of the trees. FIG. 1 shows a representative survey region 10. A forester has created a cruise grid 12, which may correspond to the outline of a piece of property or other factors. Cruise grid 12 has been subdivided into a series of plots 14. Typically, 5-20 trees and other vegetative and descriptive measures are taken within each plot. These measurements represent only a small percentage of the growth within the plot. Thus, it is important to appropriately size the plots in order to obtain a statistically reliable sample. Numerous prior art techniques are used to create plots and cruise grids. Those skilled in the art will know that plots need not be rectangular. They may be circular. Thus, the plots illustrated are merely representative of the possibilities.
Each plot 14 contains a destination point 16. Destination point 16 is a position at which data will be collected for a particular plot 14. In the view as shown, each destination point 16 lies in the center of its respective plot 14. It need not always be centered. Numerous prior art techniques are used to determine the appropriate position for a particular destination point 16. However, simply centering the destination point within the plot is common. Data will typically be collected in a fixed radius circle proximate each destination point 16.
FIG. 2 shows a plan view of cruise grid 12. Since the forester must move between destination pointsxe2x80x94often by walking or using an ATVxe2x80x94it is desirable to map the shortest route which will cover all the points. One such route is shown as cruise route 20 in the view. Planning the route must often consider ingress/egress points, such as access road 18.
In order to survey cruise grid 12, a forester would move along cruise route 20, stopping at each destination point 16. At a particular destination point, the forester takes data samples of a specific number of trees. Data collected might include diameter, height, and some indication of overall quality. All these techniques were employed using old methods. The forester typically had a paper map. He or she would estimate distances walked or occasionally measure them using standard ropes or chains. A compass was typically used for navigation. The data collected would then be manually recorded in a notebook or similar article. It is obviously important to know the forester""s position relative to the desired destination point. The manual techniques were somewhat inaccurate in this regard, but an experienced forester was able to cope well enough to produce useful results.
The wide availability of computer and Global Positioning System (xe2x80x9cGPSxe2x80x9d) technology has changed the timber cruising process. Recent GPS systems, especially those equipped with the Wide Area Augmentation System (xe2x80x9cWAASxe2x80x9d) can obtain positional accuracy of about 3 meters. Such a system allows a forester to know his or her position without resorting to survey-type navigational aids. The forester can use a hand-held GPS to precisely navigate to a series of destination points within a cruise grid.
Portable computers have likewise replaced paper notebooks for data collection. The forester can carry one of these computers along while conducting the timber cruise. Data can then be typed into the computer and stored on a disk drive for subsequent downloading to a conventional computer. The prior art thus contemplates that a timber cruise such as the one depicted can be carried out in the following fashion:
1. The forester uses computer software and data links to obtain a map of the region and define the region of timber that is to be surveyed;
2. The forester uses computer software to divide the area into a series of plots, thereby creating a cruise grid;
3. The forester defines an appropriate destination point within each plot and stores the coordinates (latitude/longitude) of each such point;
4. The forester defines a cruise route to cover the destination points;
5. The forester physically goes to the scene and navigates to the first destination point using a GPS unit;
6. The forester collects data at the first destination point;
7. The forester manually enters the location of the first destination point, the plot number, other identifying information, and the tree data collected into a portable computer; and
8. The forester repeats this process for each destination point until the cruise route is completed.
The present invention comprises an integrated data collection system which automates the collection of timber cruise data. A navigation system is integrated with a data collection system so that real-time positional data is fed directly into the data collection system. The invention guides a forester along a pre-defined cruise route and alerts the forester when a destination point is reached. The forester is then prompted to initiate a data collection cycle. Position data, cruise grid data (such as plot number), and other information is then automatically transferred from the navigation system to the data collection system. When the forester then inputs tree data (such as height, diameter, etc.), that data is automatically cross-linked to the positional and cruise grid data transferred from the navigation system.